A 2-year-old boy is brought to the emergency department by his parents who are concerned about fussiness, decreased oral intake, and a fever that has persisted for 5 days despite regular interval dosing of acetaminophen and ibuprofen throughout that time period. Temperature is 40.3°C (104.5°F) but vital signs are otherwise normal. Physical examination reveals bilateral conjunctival injection without exudate as well as erythematous, dry, and crusted lips, mouth, and tongue. Examination of the neck reveals a palpable right-sided, mobile, 2 cm anterior cervical lymph node. A maculopapular rash noted on his chest and the backs and of his hands.
If left untreated, which of the following complications is this patient at increased risk of developing?
The correct answer is:
C) Coronary artery aneurysm
Kawasaki disease is a small vessel vasculitis most often seen in children younger than 5 years of age. It is a clinical diagnosis requiring at least five days of high fever (>104°F) PLUS four of the following: a) bilateral limbic-sparing (the limbus is the area surrounding the iris) conjunctivitis without exudate; b) mucositis of the mouth and lips +/- strawberry tongue; c) unilateral cervical lymphadenopathy >1.5 cm diameter; d) maculopapular rash which can be on the trunk, face, or extremities; e) edema +/- erythema of hands and feet. It should be treated with intravenous immunoglobulin to reduce the risk of developing a coronary artery aneurysm. Aspirin is typically administered as well during the acute phase of illness, though several meta-analyses have demonstrated that aspirin does not affect aneurysm formation.
Answer choice A: Burkitt lymphoma, is incorrect. Epstein-Barr Virus, a member of the Herpesviridae family, is implicated in the carcinogenesis of Burkitt lymphoma. It is the most common etiological agent for infectious mononucleosis. Following the acute course of infection it remains latent within B-lymphocytes, capable of triggering a proliferative state.
Answer choice B: Corneal blindness, is incorrect. Corneal blindness in childhood can result from vitamin A deficiency or aphthalmia neonatorum, conjunctivitis with discharge occurring in the first 28 days of life. Responsible pathogens include Neisseria gonorrhoeae, Chlamydia trachomatis, and herpes simplex virus, which can be transmitted from the mother at birth.
Answer choice D: Mitral valve stenosis, is incorrect. Mitral valve stenosis is associated with rheumatic fever, a delayed manifestation of an untreated infection with Group A Streptococcus.
Answer choice E: Third-degree atrioventricular (AV) block, is incorrect. Untreated Lyme aisease can lead to AVV conduction delays such as third-degree A-V block, among other complications.
Key Learning Point
Kawasaki disease is a small vessel vasculitis most often seen in children younger than 5 years of age. It is a clinical diagnosis requiring at least five days of high fever (>104°F) PLUS four of the following: a) bilateral limbic-sparing (the limbus is the area surrounding the iris) conjunctivitis without exudate; b) mucositis of the mouth and lips +/- strawberry tongue; c) unilateral cervical lymphadenopathy >1.5 cm diameter; d) maculopapular rash which can be on the trunk, face, or extremities; e) edema +/- erythema of hands and feet.
